RESUMEN
BACKGROUND: Vasculogenic mimicry (VM) is an enigmatic physiological feature that influences blood supply within glioblastoma (GBM) tumors for their sustained growth. Previous studies identify NFATC3, FOSL1 and HNRNPA2B1 as significant mediators of VEGFR2, a key player in vasculogenesis, and their molecular relationships may be crucial for VM in GBM. AIMS: The aim of this study was to understand how NFATC3, FOSL1 and HNRNPA2B1 collectively influence VM in GBM. METHODS: We have investigated the underlying gene regulatory mechanisms for VM in GBM cell lines U251 and U373 in vitro and in vivo. In vitro cell-based assays were performed to explore the role of NFATC3, FOSL1 and HNRNPA2B1 in GBM cell proliferation, VM and migration, in the context of RNA interference (RNAi)-mediated knockdown alongside corresponding controls. Western blotting and qRT-PCR assays were used to examine VEGFR2 expression levels. CO-IP was employed to detect protein-protein interactions, ChIP was used to detect DNA-protein complexes, and RIP was used to detect RNA-protein complexes. Histochemical staining was used to detect VM tube formation in vivo. RESULTS: Focusing on NFATC3, FOSL1 and HNRNPA2B1, we found each was significantly upregulated in GBM and positively correlated with VM-like cellular behaviors in U251 and U373 cell lines. Knockdown of NFATC3, FOSL1 or HNRNPA2B1 each resulted in decreased levels of VEGFR2, a key growth factor gene that drives VM, as well as the inhibition of proliferation, cell migration and extracorporeal VM activity. Chromatin immunoprecipitation (ChIP) studies and luciferase reporter gene assays revealed that NFATC3 binds to the promoter region of VEGFR2 to enhance VEGFR2 gene expression. Notably, FOSL1 interacts with NFATC3 as a co-factor to potentiate the DNA-binding capacity of NFATC3, resulting in enhanced VM-like cellular behaviors. Also, level of NFATC3 protein in cells was enhanced through HNRNPA2B1 binding of NFATC3 mRNA. Furthermore, RNAi-mediated silencing of NFATC3, FOSL1 and HNRNPA2B1 in GBM cells reduced their capacity for tumor formation and VM-like behaviors in vivo. CONCLUSION: Taken together, our findings identify NFATC3 as an important mediator of GBM tumor growth through its molecular and epistatic interactions with HNRNPA2B1 and FOSL1 to influence VEGFR2 expression and VM-like cellular behaviors.
Asunto(s)
Movimiento Celular , Proliferación Celular , Glioblastoma , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B , Factores de Transcripción NFATC , Neovascularización Patológica , Proteínas Proto-Oncogénicas c-fos , Humanos , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-fos/genética , Glioblastoma/metabolismo , Glioblastoma/patología , Glioblastoma/genética , Glioblastoma/irrigación sanguínea , Línea Celular Tumoral , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/genética , Factores de Transcripción NFATC/metabolismo , Factores de Transcripción NFATC/genética , Animales , Proliferación Celular/genética , Neovascularización Patológica/metabolismo , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Movimiento Celular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Regulación Neoplásica de la Expresión Génica , Ratones , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/irrigación sanguínea , Ratones DesnudosRESUMEN
Tertiary lymphoid structures (TLS) can reflect cancer prognosis and clinical outcomes in various tumour tissues. Tumour-associated macrophages (TAMs) are indispensable components of the tumour microenvironment and play crucial roles in tumour development and immunotherapy. TAMs are associated with TLS induction via the modulation of the T cell response, which is a major component of the TLS. Despite their important roles in cancer immunology, the subtypes of TAMs that influence TLS and their correlation with prognosis are not completely understood. Here, we provide novel insights into the role of TAMs in regulating TLS formation. Furthermore, we discuss the prognostic value of these TAM subtypes and TLS, as well as the current antitumour therapies for inducing TLS. This study highlights an entirely new field of TLS regulation that may lead to the development of an innovative perspective on immunotherapy for cancer treatment.